Processing == Java + Extra Utilities

Processing Adds:– Drawing functions– Text and font manipulations– Image and video– 3D transformations– Keyboard interaction– An editor– …

• Best way to see what Processing becomes is to generate a Java program and compare– File | Export– Look in generated applet folder

• What's different?– Import of core Processing libraries– Import of numerous Java libraries– Encapsulation of code in subclass of PApplet– Explicit visibility – public, private …– Number format changes

if (random(1.0) < 0.5) -> if (random(1.0f) < 0.5f)

– color data types are converted to int– Some functions are changed

numbers = int(snumbers); -> numbers = PApplet.parseInt(snumbers);

–Added public static void main() {…

All Java programs start with at the special function … public static void main() { …

class HelloWorldApp { public static void main(String[] args) { // Display the string. System.out.println("Hello World!"); }}

The smallest program in Processingprintln("Hello World!");

The equivalent program in Java.

This must be added to the generated Java program

• PApplet– The top-level class in Processing– The class in which all your Processing code goes– Implements most of Processing's core behavior– Way down the Java hierarchy

java.lang.Object↘ java.awt.Component

↘ java.awt.Container↘ java.awt.Panel

↘ java.applet.Applet↘ processing.core.PApplet

http://processing.googlecode.com/svn/trunk/processing/build/javadoc/core/processing/core/PApplet.html

Nearly all of Java is available from Processing

http://download.oracle.com/javase/6/docs/api/